Question

The products of the following reactions \( X \) and \( Y \) respectively are Reaction: 

• A.

  

• B.

  

• C.

  

• D.

  

Hint:

- LiAlH₄ reduces carboxyl (-COOH) to primary alcohol (-CH₂OH).
- SOCl₂ converts alcohols or carboxyl groups into acid chlorides (-COCl).
- H₂ with Pd-BaSO₄ (Lindlar's catalyst) selectively reduces acid chlorides to aldehydes (-CHO).

Answer 1

The Correct Option is A

Step 1: Understanding the Reaction Sequence 
- Y undergoes reduction with LiAlH₄ and H₂O, reducing the carboxyl (-COOH) group to an alcohol (-CH₂OH). 
- X is formed when Y is treated with SOCl₂, which replaces the -OH group with -Cl (acid chloride formation). 
- X undergoes partial hydrogenation (H₂, Pd-BaSO₄), leading to the formation of an aldehyde (-CHO) group instead of complete reduction. 

Step 2: Analyzing the Given Options 
- Option (1): Correct Structure 
- Option (2): Incorrect due to presence of two -CHO groups 
- Option (3): Incorrect because both structures have incorrect functional groups 
- Option (4): Incorrect as the aldehyde formation is missing 

Step 3: Conclusion 
- Since Option (1) follows the correct reaction pathway, it is the correct answer.